Atomic layer deposition involves the deposition of successive monolayers over a substrate within a deposition chamber typically maintained at subatmospheric pressure. An exemplary such method includes feeding a single vaporized precursor to a deposition chamber effective to form a first monolayer over a substrate received therein. Thereafter, the flow of the first deposition precursor is ceased and an inert purge gas is flowed through the chamber effective to remove any remaining first precursor which is not adhering to the substrate from the chamber. Subsequently, a second vapor precursor different from the first is flowed to the chamber effective to form a second monolayer on/with the first monolayer. The second monolayer might react with the first monolayer. Additional precursors can form successive monolayers, or the above process can be repeated until a desired thickness and composition layer has been formed over the substrate.
The invention includes improvements in apparatus and methods of atomic layer depositions, whether existing or yet-to-be developed, whereby at least one monolayer is formed over a substrate.